Buggy code:
public class TrimBarManager2 { private MenuLocationURI [ ] trimAreaURIs = new MenuLocationURI [ ] { new MenuLocationURI ( "toolbar:command1" ) , new MenuLocationURI ( "toolbar:command2" ) , new MenuLocationURI ( "toolbar:vertical1" ) , new MenuLocationURI ( "toolbar:vertical2" ) , new MenuLocationURI ( "toolbar:status" ) } ; int [ ] swtSides = new int [ ] { SWT . TOP , SWT . TOP , SWT . LEFT , SWT . RIGHT , SWT . BOTTOM } ; private TrimBarManager2 . STrimBuilder fTrimBuilder ; private IMenuService fMenuService ; private boolean fDirty ; public TrimBarManager2 ( final WorkbenchWindow window ) { } public void update ( boolean force , boolean recursive , boolean hideTopTrim ) { } public void update ( boolean force , boolean recursive ) { } private void setDirty ( boolean isDirty ) { } private boolean isDirty ( ) { } private class TrimWidgetProxy extends WindowTrimProxy { private List widgets ; private TrimAdditionCacheEntry cacheEntry ; private int originalSide ; private int curSide ; private Composite parent ; public TrimWidgetProxy ( List widgets , int side , Composite parent , TrimAdditionCacheEntry entry , boolean resizeable ) { } public void dock ( int newSide ) { } public void dispose ( ) { } public int getSide ( ) { } public boolean isAtStart ( ) { } } private class STrimBuilder { private WorkbenchWindow fWindow ; private List curGroups = new ArrayList ( ) ; private Map initializedTrim = new HashMap ( ) ; public STrimBuilder ( WorkbenchWindow window ) { } public void tearDown ( ) { } public void build ( boolean hideTopTrim ) { } private void processAdditions ( MenuLocationURI trimURI , boolean hideTopTrim ) { List additions = fMenuService . getAdditionsForURI ( trimURI ) ; if ( ( additions . size ( ) ) == 0 ) return ; int swtSide = getSide ( trimURI ) ; if ( ( swtSide == ( SWT . TOP ) ) && hideTopTrim ) return ; for ( Iterator iterator = additions . iterator ( ) ; iterator . hasNext ( ) ; ) { TrimAdditionCacheEntry trimEntry = ( ( TrimAdditionCacheEntry ) ( iterator . next ( ) ) ) ; String groupId = trimEntry . getId ( ) ; List widgets = trimEntry . getWidgets ( ) ; if ( ( widgets . size ( ) ) == 0 ) continue ; Composite grpComposite = new Composite ( fWindow . getShell ( ) , SWT . NONE ) ; grpComposite . setToolTipText ( groupId ) ; RowLayout rl = new RowLayout ( ) ; rl . marginBottom = rl . marginHeight = rl . marginLeft = rl . marginRight = rl . marginTop = rl . marginWidth = 0 ; grpComposite . setLayout ( rl ) ; boolean resizeable = false ; for ( Iterator widgetIter = widgets . iterator ( ) ; widgetIter . hasNext ( ) ; ) { IWorkbenchWidget widget = ( ( IWorkbenchWidget ) ( widgetIter . next ( ) ) ) ; IConfigurationElement widgetElement = trimEntry . getElement ( widget ) ; if ( widget != null ) { <START_BUG> resizeable |= trimEntry . isResizeable ( widgetElement ) ; <END_BUG> renderTrim ( grpComposite , widget , swtSide ) ; } } TrimBarManager2 . TrimWidgetProxy groupTrimProxy = new TrimBarManager2 . TrimWidgetProxy ( widgets , swtSide , grpComposite , trimEntry , resizeable ) ; curGroups . add ( groupTrimProxy ) ; placeGroup ( groupTrimProxy ) ; } } private void placeGroup ( final TrimBarManager2 . TrimWidgetProxy proxy ) { } private void renderTrim ( final Composite groupComposite , IWidget iw , final int side ) { } private int getSide ( MenuLocationURI uri ) { } public void updateLocations ( List knownIds ) { } } public void updateLocations ( List knownIds ) { } public void dispose ( ) { } }

Fix:
resizeable |= trimEntry . fillMajor ( widgetElement ) ;